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Any roughness will improve a cylinder, or a golf ball, so the example is spurious. However, there is a lot to be said for adaptive surfaces. Organic fliers seem fond of using attached vortices to extend their performance envelope. Car bodies don't usually have such radical changes in angle of attack. Feathers also have excellent structural advantages, being surfaced with velcro-edged strips that resist tearing, but can be repaired instantly.
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